Log debarking apparatus



R. M. BAKER LOG DEBARKING APPARATUS Nov. 10, 1959 2 Sheets-Sheet 1 Filed Sept. 19, 1957 NN QNN INVENTOR Rober/M Baker ARR 31m rwmg HTTORNEYS Nov. 10, 1959 R. M. BAKER 2,912,023

LOG DEBARKING APPARATUS Filed Sept. 19, 1957 2 Sheets-Sheet 2 IN VEN TOR.

R Raber/ M. Baker United States Patent() 2,912,023 LOG DEBARKING APPARATUS Robert M. Baker, Morley, Mich., assignor of one-half to Norval K. Morey, Winn, Mich.

Application September 19, 1957, Serial No. 684,930

17 Claims. (Cl. 144-208) This invention relates to bark-removing machines for use in preparing logs or bolts for the pulp mill and pulpmg operations.

While various bark-removing machines have been designed, much of the bark which must be removed prior to the commencement of pulping operations is still removed by hand, or by fluid under pressure, in the mill, after a considerable soaking and softening period, be-

cause no really satisfactory machine has heretofore been available. Both of these methods of removing bark are slow and costly and designers have for some time sought to develop a machine which could process several cords of wood per hour at a location in the forest removed from the mill. Most of the machines which have been proposed have been of the type which scrape or abrade the bark from the bolts or logs, and such machines have proven unsatisfactory in practice. In the winter time, when the logs are frozen, the bark cannot be scraped or peeled, and so, during the season when timber is most easily transported over the ground from relatively inaccessible locations in the forest, present machines are unsatisfactory, and the logs must be stock-piled for soaking, or the bark removed by hand with great difficulty.

One of the prime objects of the instant invention is to provide a machine which removes the bark by chipping it from the log or bolt in a manner which is eflicient-at any season of the year.

Another object of the invention is to provide a machine of the character described which chips bark splinters from the log in such a manner that a minimum of horsepower is required to drive the chipping head, and which provides means, independent of the chipping head, for very simply adjusting the depth of chip to the type of wood being processed.

A further object of the invention is to provide a machine which incorporates means for yieldingly forcing the bolt into contact with the cutter members,-While at the same time spirally feeding the bolt through the machine.

Another object of the invention is to provide a machine to handle logs of varying diameter, and which need not be straight to be processed in the machine.

A further object of the invention is to provide a machine Which removes the knots from the bolt prior to the time it chips the bark therefrom as it is fed through the machine.

Another object of the invention is to provide a machine of compact and simple construction, which can be easily mounted on a trailer or the like and transported to central bolt-receiving stations where the bark is removed, thereby eliminating the need for bark-disposal apparatus and an expensive plant for receiving and removing the bark from the bolts.

Still a further object of the invention is to provide a bark-removing machine of the character described having feeding means which permit variance, of the rate of feed of the bolts through the machine.

A further object of the invention is to provide a simple and eflicient machine which is economical to manufacture 2,912,023 Patented Nov. 10, 1959 2 and. assemble, which is light and durable in character, and which can be readily installed and moved about from place to place on a small trailer or the like.

- With the above and other objects in view, the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims, it being understood that equivalent changes may be made in the various elements which comprise the invention without departing from the function thereof, or the scope of the appended claims.

In the drawings:

Fig. 1 is a top plan view of the bark-removing machine with certain elements omitted in the interests of clarity;

Fig. 2 is a side elevation thereof, the diagrammatic lines illustrating a bolt or log; and the arrows, the direction of rotation of the various elements, certain of the members being omitted in the interest of clarity.

Fig. 3 is a fragmentary, enlarged, transverse sectional view of the chipper assembly, as seen from the line 3-3 of Figure 4, and x Fig. 4 is a top plan view thereof.

Fig. 5 is an enlarged, fragmentary sectional view, being taken on the line 55 of Figure 4 and showing the spring for returning the pivotal feed rolls to position. Fig. 6 is an enlarged, fragmentary perspective view of the foot-pedal-operated lever system for lifting the feed rolls to permit insertion of a bolt in the machine, only certain of the other elements of the machine being shown.

Fig. 7 is an enlarged, fragmentary side elevation illustrating the mounting of the roller-guide-support arms which permit their adjustment. i

Fig. 8 is a fragmentary front elevation of one of-the frame members on which the feeder-Wheel assemblies are adjustably secured.

Fig. 9 is a fragmentary side elevation of the means adjustably connecting two adjacent frames of one feederwheel assembly. e

Fig. 10 is an enlarged, fragmentary isometric view of one of the chipper teeth.

Referring now more particularly to the accompanying drawings in which I have shown a preferred embodiment of the invention, a letter F generally indicates the frame of the machine which may be mounted on any suitable wheeled carrier or the like. 7 comprises side members 12 and 12a and end members 13 and 13a respectively. Mounted in bearings 14, substantially centrally of the bed or frame F, is a shaft '15 which is drivingly connected to a motor or engine 16 mounted on a platform 17 supported by the front end of the frame.

The motor 16 which is preferably a conventional internal-combustion engine, drives a jack shaft 18 which is supported by a bearing 18a through belts 19 trained around pulleys 20 and 21. on the motor shaft and jack shaft 18 respectively. A pulley 22 is mounted on the shaft 18, and drives a pulley-23 provided on shaft 15 by meansof belts 24..

Keyed on the shaft 15 are a pair of rotary cylinders 25 and 26 (see Figs. 3 and 4) carrying chipper members 27 (Fig. 10), providedwith ends which are semicylindrical in configuration and have linear edges 270! which are pref.- erably sharpened. The cylinder 25 first engages the bolt or log B shown in diagrammatic linesin Fig. 2, and knocks or cuts the limbknots therefrom, and cylinder 26 is employed to actually chip off the bark. e

The chipper members 27 are arranged, 'n three parallel rows on cylinder 26 in .a particular circumferentially staggered relation, and the purpose of this arrangementwill be later described.

spaced supporting edges 28a, is provided in advance of The frame F is open and f 2,912,023. v A

the cylinder 26 to support the bolt on one side of the chipper cylinder or head 26, and a guide 29 is also freely revolvable on the shaft 15 on the opposite side of the cylinder 26 to support the bolt B. Sleeve. bearings 30 and 31, having bores of considerably greater diameter than that required to pass shaft 15, support the roller guides 28 and 29 respectively.

The position of guide 28 determines the depth of chip removed by the chipping members 27, since it supports the bolt B at a particular level with relation to the terminal edges of chipper members 27. Fixed to sleeve 30 which supports guide 28 is an arm 32 which has an arcuate slot 32a (see Fig. 7) therein.

An angle bracket 33 on a plate 34 which spans frame members 12 and 12a, carries a bolt 35 which extends through the slot 32a, and it will be obvious that arm 32 can be raised or lowered with respect to bolt 35 so as to be adjusted to various positions. Once the sleeve 30 is at a proper height, the nut on bolt 35 is tightened down to fix the arm in position. Sleeve 31 is similarly supported by an arm 36 having a similar slot through which another bolt 35 extends, and being supported by a bracket 37.

The peripheral surface of guide roller 29 is arranged in horizontal parallelism with the edges 27a on cylinder 26 since it must support the stripped portion of the bolt, and it must support the bolt in this manner if the depth of chip is to be uniform. A pair of arcuate deflector plates 38 are also supported by the plate 34 to deflect the chipped bark material removed by the cylinders, and cause it to be deflected to a point below the frame F. Icurnaled in bearings 39 at the rear end of the machine is a shaft 40, which pivotally supports a pair of separate frames 41 and 42, formed of side frame members 4111 and 42a respectively, which are supported by the shaft 40 so as to be pivotal thereon. The separate frames 41 and 42 are provided with end plates 43 having slots 43a therein (Fig. 8). the plates 43 adjustably supporting U-shaped bearing frames 44 by means ofbolts 45, which extend through bolt openings in frames 44 and slots 43a respectively, and nuts are carried by the bolts 45 in the usual manner to secure the frames 44 in adjusted position.

The bearing frame 44 is tilted as shown, and carries a shaft 46 at an angle of about upwardly relative to a horizontal plane (from the cylinder side). Mounted and rockable with shaft 46 are a pair of rolls comprising noninfiatable hard-rubber tires 47, and these tires may also be formed of any other suitable material which will not slip, but will revolve the bolt through the machine. A pulley 48 keyed on shaft 46 drives the tires through a belt 49 and pulley 50 keyed on shaft 40, and shaft 40 is driven in a manner which will be later described.

The frame 41 is supported in angular position by the frame 42 by means of a plate 51 (see Fig. 9), which extends laterally from the inner one of the side frame members 42a and mounts a threaded lug 52 that is threaded through a plate 53 which extends laterally from that side frame member 41a adjacent the frame 42. The screw or lug 52 is swiveled to plate 51 so that it cannot move in an axial direction, but, when rotated, will adjust the frame 41 upwardly or downwardly. The bearing frame 44 on frame 42 supports a shaft 54 on which are rolls comprising tires 55, similar to the tires 47, and shaft 54 is supported at the same upward angle as shaft 46 although its inner end is below the inner end of shaft 46 so that the perip eral surface of the inner tire of the higher pair of tires 55 is substantially on a level with the peripheral surface of the inner tire of the lower pair of tires 47. The shafts 46 and 54 are not only at an angle with respect to the horizontal but are also slightly askew, about 7", with respect to a vertical plane transverse to the rails 12 and 12a of the machine and with respect to the path of travel of the bolt B, The purpose is to have the peripheral edges of the tires 47 and 55 in transverse alignment at the points where they engage the bolt, so that all tires engage and revolve the bolt at it travels in a linear path parallel with shaft 40 through the machine.

Mounted on shaft 54 is a pulley 56 which is driven by means of belt 57 from a pulley 58 on shaft 40. The frame 42 carries a nut 59 having a threaded opening therein for receiving a screw shaft 60 which supports the frame 42 in angularly adjusted position, and upon rotation of shaft 60, nut 59 and accordingly frames 42 and 44 will be raised or lowered, this operation being effected through a hand wheel (not shown) which is mounted on a shaft (not shown) extending from a gear box 61, which '64 which is journaled in bearings 65 provided on the bed F. The frames 62 and 63 similarly have end plates 43 on which bearing frames 44 are supported in the same manner as before, except that in the instant case the bearing frames are tilted downwardly at an angle of about 15 (from the cylinder 25 side) and support the shafts 66 and 67 at an angle of about 15 with respect to the horizontal. These shafts 66 and 67 each support a similar pair of noninfiatable rolls comprising tires 68 and 69 respectively which correspond to the tires 47 and 55, and will likewise be about 12 inches in diameter.

The shaft 66 is driven by a pulley 70 through belt 71 from a pulley 72 keyed on shaft 64, and shaft 67 is driven by a pulley 73 through a belt 74 trained around a pulley 74a on shaft 64. As later explained, the tires 68 and 69 are driven from the same source of power as tires 47 and 55, and in the same counterclockwise direction, as disclosed in Fig. 2, and rotate the bolt spirally through the machine in a clockwise direction, which is opposed to the direction of rotation of the cylinders 25 and 26. The shafts 66 and 67 are also tilted oppositely to shafts 46 and 54, the inner end of shaft 66 being below the inner end of shaft 67 slightly so that the periphery of the inner tire of the higher pair of tires 68 is substantially on a level with the periphery of the inner tire of the lower pair of tires 69. These shafts 66 and 67 are also skewed at an angle of about 7 to a true transverse plane so that the peripheries of all tires are in engagement with the bolt which moves crosswise through the machine. The fact that shafts 44, 54, 66 and 67 are tilted requires this skewing if the bolt is to be engaged byall the tires simultaneously.

Frames 62 and 63 are connected by plates 51 and 53 and a screw 52, and in order to raise both frames to permit entry of a bolt B, the operator need merely raise one of them. This is done by depressing a foot-pedal mechanism or the like which comprises a foot pedal 75 (see Fig. 6), which is secured to a bcllcrank lever 76. When foot pedal 75 is depressed, the portion 76a of the lever 76 is raised, because lever 76 is pivoted to the frame section 12b at 77.

The upper end 7611 of lever 76 is connected to frame 63 by means of a pin 78, and frames 62 and 63 are thus pivotal upwardly about shaft 64 when the pedal 75 is depressed.

A spring 79 is connected to a bracket 80 carried by the frame F, and to a bracket 81 carried by frame 63, said spring forcing the tires into engagement with the bolt B when the foot pedal 73 is released. A spring 79 yieldingly holds tires 69 and 68 down on bolt B with some force, and the result is that the tires do not slip on the bolt, but tend to assist tires 47 and 55 in revolving it in the direction shown in Fig. 2, so that it follows a spiral path through the machine. The tires preferably revolve the bolt at a speed of about 90 r.p.m., while the cylinders 25 and 26 are revolving at a speed of about 5000 r.p.m.

While the instant machine is designed to chip the bark from bolts within a diameter range of 2 /2 inches to two feet or more, it will be obvious that larger bolts may be accommodated by simply enlarging the various elements which have been shown and described.

The shaft 64 which drives tires 68 and 69 may, if desired, be driven from shaft 18 through a speed reducer 82; pulleys 83 and 84, and a belt 35 drivingly connecting the shaft 18 with the input shaft 86 of the reducer 82.

The output shaft 87 of the reducer can be coupled to the shaft 64 in any suitable manner, and as'presently shown, a pulley 88 is mounted on shaft 64 to drive shaft 40 through a belt 89 which trains around a pulley 90 on the shaft 40. An idler pulley 91 may be supported for free rotation on a stub shaft 92 projecting from side frame member 12:: and reducer 82 can be supported by an arm 93 hinged to rail 12a at 94.

The spring 79 which holds the tires on frames 62. and

63 in engagement with the log or bolt will permit the frames 63 and 64 to lift as may be necessary until the cylinder 25 has removed any projecting knots or the like, and a rubber bumper 95 is mounted on shaft 96 provided on plate member 120, and prevents frames 62 and 63 from returning below a certain predetermined position.

In operation, the operator feeds on end of a bolt which may be 20 feet, or more, in length, into the nip between the tires 68 and 47, while pressing foot pedal 75 to hold tire assemblies 62 and 63 above their normal position, so that the log can be fed in axially under tires 68. The foot pedal 75 is then released permitting tires 68 to snap back into a position in which the outer tire 68 engages the log or bolt B under the action of spring 79. Because the frames 62 and 63 are tilted downwardly in a transverse direction from the cylinder 25 side while frames 41 and 42 are tilted upwardly, the bolt is moved smoothly through the machine by all of the tires without slippage.

In this feeding operation the tires do not remove any bark, nor is this their purpose, the cylinder 26 being relied upon to remove the bark, but before that the cutter head 25 will knock the knots from the bolt without chipping bark from the body of the bolt since the cylinder 25 is of lesser diameter than head 26, and the members 27 on head 25 project just sufliciently to barely touch the surface of the bolt as it travels through the machine. It will therefore be apparent that cylinder 25 is easily driven and requires only sufficient power to remove the knots and knobs.

The usual depth of cut will vary from /2 inch for hardwoods such as oak, to of an inch for cedar. As noted, the cutters 27 are staggered circumferentially on cylinders 25 and 26 so that only one is in engagement with a bolt at one time, and the stripper plate 29 prevents any build up of bark at this point.

The bolt B moves spirally, slowly past the cutter heads 25 and 26. Since the force of the heavy spring 79 bearing on the bolt is considerable, the noninflatable tires 68 and 69 are urged against the bolt with considerable force during its travel through the machine, however, if the bolt varies in diameter, the fact that the frames 63 and 64 are resiliently mounted permits them to raise or lower as necessary. Further, when the cylinder 25 encounters an obstruction which it cannot immediately knock off, the fact that frames 62 and 63 can pivot upwardly provides a safety factor.

Because the pairs of shafts 66 and 67, and 46 and 54 are pitched, they must also be skewed with respect to shaft 15, if all of the tires are to simultaneously engage the bolt, therefor, shafts 66 and 67 are pitched'inwardly toward the axis of shaft 15 slightly, from the charge end of the machine at cylinder 25, whereas the axes of shafts 44 and 54 are pitched slightly away from the axis of shaft 15 from the charge end of the machine at cylinder 25 because tires 55 are at the higher level.

The level of edges 28a of roller 28 with respect to the level of the cutting edges of members 27, determines the depth of cut, and the supporting surface of disk 29 will be at the same level as the cutting edge of the members 27, since it must support the portion of the bolt from which the bark has been peeled. Surfaces 28a will normally be a spaced distance below the cutting edges of members 27 on the cylinder 26, this governs the depth or thickness of the chips to be removed. The members 27 on cylinder 25 will,.of course, be at approximately the same level as edges 28a.

It will be seen that the rows of members 27 on cylinder 26 are staggered such that a cutter in the left row (in Fig. 3) first removes a chip, after which a cutter 27 in the outer row, at the right, removes a chip, and thence a cutter 27 in the middle row chips out a bark area between the two previous chips. In each instance only one member 27 on the entire cylinder 26 is chipping at one time, and each chip is removed before another chip is engaged. It has been found that this method of chipping provides far better results than if successive chips along the length of the bolt were simply removed in sequence. The fact that the bolt B is slowly spiralling does not affect this method of chipping, since the cutter cylinder 26 travels at such a high rate of speed with respect to the axial travel of the bolt. Each of the splinters or chips removed will be less than an inch long. The chippers 27 on cylinder 26 may be arranged so that the rows are slightly axially spaced (as exaggerated in the drawings) or may be arranged so that the chippers 27 in successive rows are not axially spaced.

It should be apparent that I have perfected a thoroughly practical machine which requires very little horsepower to operate, andcan be readily moved about to various locations in the woods and forests as desired. It is to be understood that various equivalent changes may be made in the invention without departing from the scope of the claims and that in all cases the specifications and descriptive matter are to be interpreted as illustrative rather than as in any way limiting.

What I claim is:

1. In a bolt-debarking apparatus, a frame; support means on said frame for guiding a bolt in a path of travel from a feed side of the frame to a discharge side, means 7 moving a bolt spirally as it travels; and a chipper cylinder substantially axially parallelwith said path of travel of the bolt, said cylinder having circumferentially staggered chippers thereon, said means for spirally moving a.

tion.

2. The combination defined in claim 1 in which said support means is at a slightly lower level atthe. feed end than at the discharge end.

3. The combination defined in claim 1 in which said sets of rolls are also skewed with respect to the path of travel of a bolt through the apparatus.

4. The combination defined in claim 1 in whichfsaid cylinder is mounted on a transversely disposed shaft and said support means comprises disks on both sides of said cylinder, said disks having openings considerably enlarged in diameter over said shaft through which said shaft passes; and means adjustably supporting said disks in different positions of vertical disposition relative to said shaft in accordance with the thickness of chips to b removed.

5. The combination defined in claim 4 in which pivotal arms are adjustably secured on said frame to support said disks.

6. In bolt-debarking apparatus; a longitudinal main frame; a first generally centrally and transversely disposed shaft on said main frame; a chipper cylinder fixed on said first shaft; means for driving said first shaft; another shaft on each side of said first shaft generally parallel thereto and at a spaced distance therefrom; a sub-frame on both of said latter shafts and extending at an upwardly inclined angle relative to said main frame toward the central portion thereof; each sub-frame at its inner end, carrying a cross shaft transverse to the sub-frame positioned above the cylinder, transversely spaced bolt-feedrolls on each of said cross shafts at the inner ends of said sub-frames with the rolls defining a bolt-feeding nip between them, means for driving each of the shafts on which the sub-frames are mounted; and means on said shafts on which the sub-frames are mounted for driving the cross shafts on which said rolls are mounted, so that a bolt is fed spirally through the machine while said chipper cylinder operates to chip the bark therefrom.

7. In a bolt debarking apparatus; frame means having a charge side to which bolts are supplied endwise and a discharge side from which they are removed; support means on said frame for guiding a bolt in a path of travel from the charge side to the discharge side of the frame means; means supported by said frame means above said support means for moving a bolt lengthwise spirally in a path of travel from the charge side toward the discharge side; said means comprising at least a pair of rotatable, bolt moving, roll members having axes extending in a generally horizontal direction, said roll members being horizontally spaced to provide a nip between them and permit them to engage opposite sides of a bolt; one of said roll members being vertically inclined in one direction and the other being vertically inclined in the.

other direction; a rotatable chipper member mounted by said frame means and extending generally axially parallel to said bolt moving members and the path of travel of a bolt in the nip formed between them, said chipper mem ber having axially staggered, circumferentially spaced, outwardly extending chippers thereon; said chipper member being mounted under said nip between the rotatable bolt moving members; means supported by said frame means for rotating said bolt moving members in the same direction of rotation; and means supported by said frame means for rotating said chippermember in the opposite direction of rotation.

8. The combination defined in claim 7 in which said chippers comprise semicylindrical radially projecting members having cutting edges at their linear upper edge.

9. In a bolt embarking apparatus; frame means having a charge side and a discharge side; support means on said frame for guiding a bolt in a path of travel from the charge side to the discharge side of the frame means,

der mounted by said frame means generally axially parallet to said roll members and the path of travel of a bolt in the nip between them, and mounted coextensively with said roll members and vertically adjacent the nip formed between them, said cylinder having circumferentially spaced, outwardly extending chippers mounted thereon for chipping bark from a bolt moved spirally endwise by said roll members; and means mounted by said frame means for driving said rotatable roll members in the same direction of rotation.

10. The combination defined in claim 9 in which said chipper cylinder is mounted on shaft means for driving the same and a bark removing section having outwardly extending chippers is also mounted by said shaft means; said chippers on the chipper cylinder being outward radially of the chippers on the bark removing section.

11. The combination defined in claim 9 in which said chippers comprise radially projecting chipper tines provided with linear chipping edges.

12. The combination defined in claim 9 in which the chippers are disposed generally in axially spaced rows with the chippers in each row circumferentially staggered with respect to the chippers in the other rows.

13. The combination defined in claim 12 in which the chippers in rows on opposite sides of the row between them are closest in circumferential spacing so that bark chips are removed on each side of a bark surface by said rows on opposite sides prior to chipping out said surface.

14. The combination defined in claim 9 in which a subframe assembly carrying one of said roll members is movably mounted on said frame means for movement toward and away from said other roll member; and resilient means opposes movement of said sub-frame assembly in a direction to move said one roll member away from the other roll member.

15. The combination defined in claim 9 in which a subframe assembly carrying one of said roll members is supported by said frame means for axial tilting adjustment of said one of said roll members on said frame means; and means for securing said sub-frame assembly in various tilted positions.

16. The combination defined in claim 9 in which shaft means is supported by said frame means; a sub-frame carrying'one of said roll members is pivotally supported by said shaft means for swinging movement to move said one of said roll members toward and away from the other roll member; means for mounting said one of said roll members for tilting movement in an axial plane is provided; and means for securing said latter roll member in tilted positions.

17. The combination defined in claim 9 in which said support means on said frame for guiding a bolt in a path of travel from the charge side to the discharge side of the frame means includes members near the charge side and discharge side, with the member near the charge side at a slightly higher level than the member near the discharge side to guide the bolts travel relative to the chipper cylinder and its outwardly extending chippers as the bolt moves spirally endwise.

References Cited in the file of this patent UNITED STATES PATENTS 532 McMillen Dec. 26, 1837 987,828 Schenck Mar. 28, 1911 1,373,243 Hellstrom Mar. 29, 1921 2,642,904 Pearce June 23, 1953 2,726,691 Harwood et al Dec. 13, 1955 2,733,742 Bedard Feb. 7, 1956 2,794,464 Meiklejohn June 4, 1957 2,800,935 Hosmer July 30, 1957 

